Sales of coal, lubricating oil, metal materials, building materials, electrical equipment, primary agricultural products, food and daily necessities; Warehousing (excluding dangerous goods), general road transportation of goods, landscaping projects, steel structure projects, design and construction of housing construction projects, construction labor subcontracting, installation of communication equipment (excluding radio receiving equipment), electronic products, development of computer software and hardware technology, self-operation and agency of import and export of all kinds of goods and technologies (restricted or prohibited by the state for companies to operate or import and export) Excluding goods and technologies. (Business activities subject to approval in accordance with the law may only be carried out after approval by the relevant authorities. ) General items: Sales of chemical products (excluding chemical products subject to licensing); Sales of metal matrix composites and ceramic matrix composites (except for projects that require approval by law, business operations are carried out independently based on the business license in accordance with the law)